HP- Containment hydrogen control Flashcards
What is the flow path of the HP hydrogen purge subsystem? What is the purpose of the unit heater?
pressurized air flows into the hydrogen purge unit, and through a mist eliminator and unit heater. after the heater, air passes through a HEPA filter, a carbon filter, and another HEPA filter and goes to the plant vent
keep humidity below 70%
How would the Hydrogen Monitoring Subsystem be affected if HC was not in operation?
The air in containment would not be mixed well which would give a false reading when the analyzers are placed in service
The Hydrogen Recombiner Standby Space Heaters receive Non-Class 120 VAC operating power from what system?
Lighting Power panel (QB)
What is the auto feature that will isolate the HP hydrogen purge exhaust subsystem?
CIAS
recombiner inlet and outlet also serve the hydrogen purge exhaust system
What is the power supply for the Hydrogen Analyzers and sample pump?
PH
Following a LOCA, what are some ways that Hydrogen is produced inside containment?
Metal-water reaction involving the zirconium fuel cladding and the reactor coolant
Radiolytic decomposition of the Post-LOCA emergency cooling solutions
Corrosion of metals and paints by solutions used for emergency cooling or containment spray
How long do I have to make the Hydrogen Recombiner operable?
100 hours of the same LOCA
What components makeup the Hydrogen Purge Exhaust Subsystem?
Mist eliminator, heater, HEPA filters, Carbon adsorber
In order to align the HP hydrogen purge subsystem to containment, what is the maximum temperature and pressure?
180*F and 10 psig
or when hydrogen concentration reaches 3.5% volume
What powers the Hydrogen Purge Exhaust Electric Duct Heater?
NH
What is the purpose of the Containment Hydrogen Monitoring subsystem? How many redundant trains are there and what does each train consist of?
Measure the hydrogen concentration at two independent locations and to alert the operator in the control room of the need to activate the hydrogen recombiners or Hydrogen Purge system
two, hydrogen sensor, electronic subassembly, local and remote readout/alarms
Where is the sample line for the Hydrogen Analyzer? Where are the Hydrogen analyzers located?
Taps off the suction line to the hydrogen recombiner, which is coming from containment, passes through the analyzer and returns to the containment
aux. building
Where do the hydrogen recombiners receive power from? What provides the power distribution and control instrumentation and how is it connected to the recombiner?
PH and PK
power and control console
connected by portable cables
What is the airflow rate through the Hydrogen Purge Exhaust?
50 cfm
What is the purpose of the Hydrogen Recombiner Subsystem? What is the backup subsystem in the case that both recombiners fail?
Provides the primary means of reducing containment hydrogen concentrations after a LOCA
HP hydrogen purge exhaust